ASoC: rsnd: Support hyphen or dot in indexed clock and reset names

The rsnd driver historically looks up per-instance clocks and resets
using dot-separated names matching the ones declared in R-Car device
tree bindings ("ssi.0", "src.0", "adg.ssi.0", ...). The dot separator
is unusual for device tree clock-names / reset-names and newer
Renesas SoC bindings (RZ/G3E and later) use the more standard hyphen
form ("ssi-0", "src-0", ...).

Rather than force every existing R-Car user to rename their DT entries,
add a small set of helpers that try the hyphen form first and fall
back to the dot form. While at it, convert the existing indexed
devm_clk_get() call sites in the SSI, SRC, CTU, DVC and MIX probes to use
the new helpers and drop the now unused per-module name buffers and
NAME_SIZE defines.

Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/20260525110230.4014435-5-john.madieu.xa@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: John Madieu

sound/soc/renesas/rcar/core.c

@@ -1232,6 +1232,73 @@ int rsnd_node_count(struct rsnd_priv *priv, struct device_node *node, char *name
 	return i;
 }
 
+/*
+ * Build "<base>-<index>" or "<base>.<index>" and try the hyphen form first,
+ * falling back to the dot form if the hyphen form is not present. This lets
+ * the driver accept both the new DT convention ("ssi-0", "src-0", ...) and
+ * the legacy R-Car convention ("ssi.0", "src.0", ...) transparently.
+ *
+ * @base: name prefix ("ssi", "src", "ctu", "mix", "dvc", "adg.ssi", ...)
+ * @index: integer suffix
+ *
+ * On -ENOENT from the hyphen form, the dot form is tried. All other errors
+ * (including -EPROBE_DEFER) are returned to the caller unchanged, so
+ * behaviour against the clock and reset frameworks is preserved.
+ */
+#define RSND_INDEXED_NAME_MAX	32
+
+static void rsnd_format_indexed_name(char *buf, size_t buflen, char sep,
+				     const char *base, int index)
+{
+	snprintf(buf, buflen, "%s%c%d", base, sep, index);
+}
+
+struct clk *rsnd_devm_clk_get_indexed(struct device *dev,
+				      const char *base, int index)
+{
+	char name[RSND_INDEXED_NAME_MAX];
+	struct clk *clk;
+
+	rsnd_format_indexed_name(name, sizeof(name), '-', base, index);
+	clk = devm_clk_get(dev, name);
+	if (!IS_ERR(clk) || PTR_ERR(clk) != -ENOENT)
+		return clk;
+
+	rsnd_format_indexed_name(name, sizeof(name), '.', base, index);
+	return devm_clk_get(dev, name);
+}
+
+struct clk *rsnd_devm_clk_get_optional_indexed(struct device *dev,
+					       const char *base, int index)
+{
+	char name[RSND_INDEXED_NAME_MAX];
+	struct clk *clk;
+
+	rsnd_format_indexed_name(name, sizeof(name), '-', base, index);
+	clk = devm_clk_get_optional(dev, name);
+	if (IS_ERR(clk) || clk)
+		return clk;
+
+	rsnd_format_indexed_name(name, sizeof(name), '.', base, index);
+	return devm_clk_get_optional(dev, name);
+}
+
+struct reset_control *
+rsnd_devm_reset_control_get_optional_indexed(struct device *dev,
+					     const char *base, int index)
+{
+	char name[RSND_INDEXED_NAME_MAX];
+	struct reset_control *rstc;
+
+	rsnd_format_indexed_name(name, sizeof(name), '-', base, index);
+	rstc = devm_reset_control_get_optional(dev, name);
+	if (IS_ERR(rstc) || rstc)
+		return rstc;
+
+	rsnd_format_indexed_name(name, sizeof(name), '.', base, index);
+	return devm_reset_control_get_optional(dev, name);
+}
+
 static struct device_node*
 	rsnd_pick_endpoint_node_for_ports(struct device_node *e_ports,
 					  struct device_node *e_port)

sound/soc/renesas/rcar/ctu.c

@@ -6,7 +6,6 @@
 
 #include "rsnd.h"
 
-#define CTU_NAME_SIZE	16
 #define CTU_NAME "ctu"
 
 /*
@@ -319,7 +318,6 @@ int rsnd_ctu_probe(struct rsnd_priv *priv)
 	struct device *dev = rsnd_priv_to_dev(priv);
 	struct rsnd_ctu *ctu;
 	struct clk *clk;
-	char name[CTU_NAME_SIZE];
 	int i, nr, ret;
 
 	node = rsnd_ctu_of_node(priv);
@@ -350,10 +348,7 @@ int rsnd_ctu_probe(struct rsnd_priv *priv)
 		 * CTU00, CTU01, CTU02, CTU03 => CTU0
 		 * CTU10, CTU11, CTU12, CTU13 => CTU1
 		 */
-		snprintf(name, CTU_NAME_SIZE, "%s.%d",
-			 CTU_NAME, i / 4);
-
-		clk = devm_clk_get(dev, name);
+		clk = rsnd_devm_clk_get_indexed(dev, CTU_NAME, i / 4);
 		if (IS_ERR(clk)) {
 			ret = PTR_ERR(clk);
 			goto rsnd_ctu_probe_done;

sound/soc/renesas/rcar/dvc.c

@@ -29,7 +29,6 @@
 
 #include "rsnd.h"
 
-#define RSND_DVC_NAME_SIZE	16
 
 #define DVC_NAME "dvc"
 
@@ -327,7 +326,6 @@ int rsnd_dvc_probe(struct rsnd_priv *priv)
 	struct device *dev = rsnd_priv_to_dev(priv);
 	struct rsnd_dvc *dvc;
 	struct clk *clk;
-	char name[RSND_DVC_NAME_SIZE];
 	int i, nr, ret;
 
 	node = rsnd_dvc_of_node(priv);
@@ -354,10 +352,7 @@ int rsnd_dvc_probe(struct rsnd_priv *priv)
 	for_each_child_of_node_scoped(node, np) {
 		dvc = rsnd_dvc_get(priv, i);
 
-		snprintf(name, RSND_DVC_NAME_SIZE, "%s.%d",
-			 DVC_NAME, i);
-
-		clk = devm_clk_get(dev, name);
+		clk = rsnd_devm_clk_get_indexed(dev, DVC_NAME, i);
 		if (IS_ERR(clk)) {
 			ret = PTR_ERR(clk);
 			goto rsnd_dvc_probe_done;

sound/soc/renesas/rcar/mix.c

@@ -32,7 +32,6 @@
 
 #include "rsnd.h"
 
-#define MIX_NAME_SIZE	16
 #define MIX_NAME "mix"
 
 struct rsnd_mix {
@@ -291,7 +290,6 @@ int rsnd_mix_probe(struct rsnd_priv *priv)
 	struct device *dev = rsnd_priv_to_dev(priv);
 	struct rsnd_mix *mix;
 	struct clk *clk;
-	char name[MIX_NAME_SIZE];
 	int i, nr, ret;
 
 	node = rsnd_mix_of_node(priv);
@@ -318,10 +316,7 @@ int rsnd_mix_probe(struct rsnd_priv *priv)
 	for_each_child_of_node_scoped(node, np) {
 		mix = rsnd_mix_get(priv, i);
 
-		snprintf(name, MIX_NAME_SIZE, "%s.%d",
-			 MIX_NAME, i);
-
-		clk = devm_clk_get(dev, name);
+		clk = rsnd_devm_clk_get_indexed(dev, MIX_NAME, i);
 		if (IS_ERR(clk)) {
 			ret = PTR_ERR(clk);
 			goto rsnd_mix_probe_done;

sound/soc/renesas/rcar/rsnd.h

@@ -476,6 +476,25 @@ int rsnd_runtime_is_multi_ssi(struct rsnd_dai_stream *io);
 int rsnd_runtime_is_tdm(struct rsnd_dai_stream *io);
 int rsnd_runtime_is_tdm_split(struct rsnd_dai_stream *io);
 
+/*
+ * Indexed clock and reset name helpers.
+ *
+ * Historically the rsnd driver has looked up per-instance clocks and
+ * resets using dot-separated names (e.g. "ssi.0", "src.0", "adg.ssi.0").
+ * Newer Renesas SoC bindings (RZ/G3E and later) use hyphen-separated
+ * names ("ssi-0", "src-0", ...) to follow the standard Device Tree
+ * naming convention. These helpers look up the hyphenated name first
+ * and transparently fall back to the dotted name, so a single driver
+ * build supports both conventions.
+ */
+struct clk *rsnd_devm_clk_get_indexed(struct device *dev,
+				      const char *base, int index);
+struct clk *rsnd_devm_clk_get_optional_indexed(struct device *dev,
+					       const char *base, int index);
+struct reset_control *
+rsnd_devm_reset_control_get_optional_indexed(struct device *dev,
+					     const char *base, int index);
+
 /*
  * DT
  */

sound/soc/renesas/rcar/src.c

@@ -39,7 +39,6 @@ struct rsnd_src {
 	int irq;
 };
 
-#define RSND_SRC_NAME_SIZE 16
 
 #define rsnd_src_get(priv, id) ((struct rsnd_src *)(priv->src) + id)
 #define rsnd_src_nr(priv) ((priv)->src_nr)
@@ -715,7 +714,6 @@ int rsnd_src_probe(struct rsnd_priv *priv)
 	struct device *dev = rsnd_priv_to_dev(priv);
 	struct rsnd_src *src;
 	struct clk *clk;
-	char name[RSND_SRC_NAME_SIZE];
 	int i, nr, ret;
 
 	node = rsnd_src_of_node(priv);
@@ -750,16 +748,13 @@ int rsnd_src_probe(struct rsnd_priv *priv)
 
 		src = rsnd_src_get(priv, i);
 
-		snprintf(name, RSND_SRC_NAME_SIZE, "%s.%d",
-			 SRC_NAME, i);
-
 		src->irq = irq_of_parse_and_map(np, 0);
 		if (!src->irq) {
 			ret = -EINVAL;
 			goto rsnd_src_probe_done;
 		}
 
-		clk = devm_clk_get(dev, name);
+		clk = rsnd_devm_clk_get_indexed(dev, SRC_NAME, i);
 		if (IS_ERR(clk)) {
 			ret = PTR_ERR(clk);
 			goto rsnd_src_probe_done;

sound/soc/renesas/rcar/ssi.c

@@ -21,7 +21,6 @@
 #include <linux/of_irq.h>
 #include <linux/delay.h>
 #include "rsnd.h"
-#define RSND_SSI_NAME_SIZE 16
 
 /*
  * SSICR
@@ -1163,7 +1162,6 @@ int rsnd_ssi_probe(struct rsnd_priv *priv)
 	struct rsnd_mod_ops *ops;
 	struct clk *clk;
 	struct rsnd_ssi *ssi;
-	char name[RSND_SSI_NAME_SIZE];
 	int i, nr, ret;
 
 	node = rsnd_ssi_of_node(priv);
@@ -1198,10 +1196,7 @@ int rsnd_ssi_probe(struct rsnd_priv *priv)
 
 		ssi = rsnd_ssi_get(priv, i);
 
-		snprintf(name, RSND_SSI_NAME_SIZE, "%s.%d",
-			 SSI_NAME, i);
-
-		clk = devm_clk_get(dev, name);
+		clk = rsnd_devm_clk_get_indexed(dev, SSI_NAME, i);
 		if (IS_ERR(clk)) {
 			ret = PTR_ERR(clk);
 			goto rsnd_ssi_probe_done;